Thats GINA and its not a custom UI. Its a log monitor that you setup triggers to do various things to include timing buffs
Theres a lot of videos on how to set it up, here is one of them
https://www.youtube.com/watch?v=Cy8YEoALMyA
GINA site where you can download it:
https://eq.gimasoft.com/gina/Default.aspx